The Upper Souris River was placed on the Environmental Protection Agencies (EPA) impaired waters list for low dissolved oxygen (DO). A Total Maximum Daily Load (TMDL) study was conducted to determine possible causes of DO depletion. From sampling and site visits it was determined nonpoint sources contributed the majority of organic loadings to the Upper Souris River. Through preliminary testing, it was determined that sediment oxygen demand (SOD) played a key role in depleting DO levels during winter months and required further investigation. River profile surveying, water quality sampling, and laboratory testing of SOD were carried out to determine parameters required for water quality modeling. SOD tests were conducted to determine impacts of sediment organic contents and temperature on SOD rate. Sediment oxygen demand rates ranged from 0.37 to 1.22 g O2/m2/d. The QUAL2K model was calibrated to simulate DO variations along the study reach under ice covered conditions.

Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2019 / Freshwater ecosystems in South Africa are losing their quality and quantity over time due to pollution mainly from mining, agriculture, industries, deforestation, sewage systems, construction of dams, channel modification and over extraction of water. The Dwars River, a tributary of the Olifants River, is of no exception, as recent studies indicated an increase in nutrient input possibly from agriculture. The Dwars River is an important source of water for nearby communities (Ga-Mampuru). The aim of the study was to assess water and sediment quality of the Dwars River using macroinvertebrates as bioindicators of pollution. Water and macroinvertebrates sampling were done seasonally from July 2017 to May 2018. The water quality results indicated that non-toxic constituents such as salinity and EC (Electrical Conductivity) were above permissible limits stipulated by the DWAF (1996) guidelines. More sensitive taxa were found upstream, despite high concentrations of some nutrients and metals in the water column. The high abundance and distribution of macroinvertebrates observed upstream was confirmed by the Canonical Correspondence Analysis (CCA), South African Scoring System (SASS5) and Average Score Per Taxon (ASPT) results during the study. Site 1 was dominated by the most sensitive taxa and this could be due to high dissolved oxygen content and increased heterogeneity of the area. Site 4 was dominated by the most tolerant taxa, according to the CCA, SASS score and ASPT results. This could possibly be due to the nutrients and heavy metals washed from upstream, which get adsorbed by the sediment. The results for species abundance, diversity and richness indicated that Ephemeroptera was the most abundant, while Diptera was the most diverse. Ephemeropterans are known to be indicators of good water quality. Site 1 had the highest number of families and orders while site 4 had the least families and orders. Ephemeroptera, Plecoptera and Tricoptera (EPT) taxa richness and Shannon diversity (H’) index values are high upstream and decrease downstream. Overall, the SASS5 indices, CCA and physicochemical results indicated that the water quality in the Dwars River is deteriorating in most impacted sites / National Research Foundation (NRF) and VLIR

Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2018 / This study aimed to determine the effects of water and sediment quality on fish and the effects of land-use on the water and sediment quality of the Steelpoort River system. To achieve these aims, a few objectives had to be met. The water and sediment quality, the level of metal bioaccumulation of two fish species, the level of acetylcholine esterase inhibition in fish brain tissue, as well as changes in land-use over time. The study adds value in the scientific knowledge of the Steelpoort catchment given that there’s little information about it. It is thus a good baseline, which gives direction for further studies conducted within this catchment. The Steelpoort River, is a tributary of the Olifants River system. The Olifants River (Mpumalanga and Limpopo provinces) is a river stressed by anthropogenic activities with the Steelpoort River being a major sub-catchment. The Steelpoort catchment is filled with mines, agricultural activities, and other developments, such as, the construction of a new dam (De Hoop Dam opened 2014), residential areas and malls. The mines within the catchment are mostly platinum and chrome mines. Sampling was conducted for high and low flow at five sampling sites: Two upstream sites, 1 and 2, and three downstream sites 3, 4, and 5. Site 1 is the reference site for the study as this section (ecoregion) was described as “least threatened”. It was hypothesised that high concentrations of metals and nutrients would be present in the water and sediment, and that the metal would be present in fish tissue and would have an effect on human health, that the biomarker AChE would show signs of inhibition within brain tissue, and lastly that land-use characteristics would have an effect on the water and sediment quality, and inhibition of AChE. Water and sediment samples were collected quarterly over a period of a year at five sites, whereas fish samples (Chiloglanis pretoriae and Labeobarbus marequensis) were only collected bi-annually at three sites. The physico-chemical, nutrients, cations and ions, and metals and metalloids were determined. The two fish species were used for metal bioaccumulation and AChE analyses. Human health risk and bio-concentration factor (BCF) analyses were conducted. Using the land-cover details obtained from South African National Biodiversity Institute (SANBI), Department of Environmental Affairs (DEA) and The Council for Scientific and Industrial Research (CSIR), land-use characteristics were determined and evaluated. The in-situ physico-chemical parameters assessed in this study were found to be within acceptable limits of the Target Water Quality Range (TWQR) at all the sites. The Electrical Confuctivity (EC) and Total Disolved Solids (TDS) parameters were highest at Site 5 and lowest at Site 1, this could be due to Site 5 being the last site before the Steelpoort River connects to the Olifants River, hence this site recieves all the ions and solutes from upstream; and the lowest value at Site 1 could be attributed to this site having the least number of lan-use effects. For nutrients, the highest total nitrogen concentration was recorded at Site 5 and the highest phosphate concentration at Site. This river is mesotrophic according to both the total inorganic nitrogen and phosphorus levels. Metals in the water column that were above DWAF guidelines for Aquatic Ecosystems were Al, Ba, Mn and Zn. In the sediment the following metals were above the Canadian sediment quality guidelines: Cd, Cu, Cr and Zn, which can pose a threat to the health of fish through biomagnification through the food chain. Both C. pretoriae and L. marequensis had bioaccumulated metals from the river system. The concentrations of metals in the muscle tissue of C. pretoriae where higher and this could be due to the fact that unskinned samples were used in the case of C. pretoriae. A variety of metals were present in both fish species but Al, Fe, Sr and Zn were present in higher concentrations. Concentrations of metals were highest in samples from Site 5 The human health risk assessment revealed that Pb could cause health related impacts to the humans who consume a single 150 g fish meal once a week in C. pretoriae; and that Co could cause potential risks in the near future. The BCF values revealed that there were more bioconcentrated metals in C. pretoriae than in L. marequensis and this could also be due to different diets. The AChE activity was higher for L. marequensis during high flow at all sites and higher at Site 1 during low flow but lower at Site 5 and equivalent at Site 2 than the AChE activity recorded for C. pretoriae. This could be due to the ability of L. marequensis to expel pesticides from their system before the pesticides affect brain activity by decreasing the function of AChE. Both fish species had more AChE activity during low flow for sites 1 and 2 than during high flow. The high flow AChE activity was higher for Site 5 in both fish species. The results confirm the hypotheses were that metals would be present in fish tissue and would have an effect on human health; and that the biomarker AChE would show signs of inhibition within brain tissue. The agricultural activity has decreased over time within the catchment, from 2000 to 2014 and this could be due to a decrease of fertile land. There has also been a decrease in the mining activity from 2000 to 2009 and then an increase during 2014, where the decrease could be due to the closure of mines at the end of their life span; and the increase in 2014 could be due to the opening of new mines. Residential areas have increased from 2000 through to 2014. The availability of water decreased from 2000 to 2009, and then increased drastically in 2014. The drastic increase is due to the multiple dams that have been built over time in order to provide water resources to the increased population, and also for mining and irrigation purposes. The water quality showed an increase in the NO3, SO4 and PO4; meanwhile the EC has decreased over time. The decrease in EC means that there are fewer ions in the river. The increase in phosphates and nitrates could mean there is a lot of fertilizers and pesticides being used in agriculture even with the decrease in agricultural land-use over the years. The pesticides can also be due to the increase in residential areas, where pesticides are also used to get rid of pests.

Thesis (M.Sc. (Zoology)) -- University of Limpopo, 2017 / In this study data was collected to establish if the water and sediment quality of the Steelpoort River has any effects on macro-invertebrate species. The Steelpoort River is a tributary of the Olifants River system but not much data about the water quality is available. The Steelpoort River is a perennial river (Ashton et al. 2001) situated west of Burgersfort and from there it flows in a north- easterly direction and converges with the Olifants River in the Drakensberg near Kromellenboog. High silt levels in the river, increases the risk of flooding and leads to the smothering of in-stream habitats resulting in loss of some invertebrate and fish species. Sampling of the water, sediment and macroinvertebrates was conducted quarterly at the Steelpoort River at five sites. One site was above the impoundment (De Hoop Dam) and the rest were below the impoundment. A handheld YSI 556™ Multi Probe System (MPS instrument and a Mettler Toledo SevenGo™ conductivity meter were used to measure the physico-chemical characteristics at the sites. The macroinvertebrates were sampled using the SASS 5 bio-assessment protocol (Goodyear & McNeill 1999, Dickens & Graham 2002). Macro-invertebrate samples were collected using a 400 mm x 400 mm SASS net with a 250 μm mesh size. The substrate was disturbed for a period of two minutes to free macro-invertebrates from the substrate. The SASS score for each site was evaluated in the field for three of the five samples. The macro-invertebrate samples were preserved in 70% ethanol and sorted to family level in the University of Limpopo’s Biodiversity laboratory. For the majority of the physico-chemical parameters the most elevated were detected downstream and lowest concentrations were detected upstream. Analysis of variance (ANOVA) indicated that there were no significant differences for electrical conductivity, salinity, and TDS, between the sites (p>0.05). There were however significant differences in the temperature, dissolved oxygen, turbidity, and pH concentrations (p<0.05). The majority of the metals and metalloids in the water (Fe, Mn, V, Co, Zn, Ba, and Cu) were highest at Tiershoek (Site1) and lowest at Steelpoort (Site 4) and Burgersfort Bridge (Site 5).The mean metal concentrations collected showed elevated levels for chromium, copper and zinc, which were above the CCME sediment guidelines. The most abundant macroinvertebrates were from the family Ephemeroptera which are pollution sensitive and good indicators of pollution in aquatic ecosystems. When using the interpretation of the SASS 5 results from Chutter 1995, the mean Average Score Per Taxa (ASPT) scores show that the water quality for Tiershoek (Site 1) and Polopark (Site 3) is natural but the habitat diversity has been reduced. For De Hoop (Site 2) and Steelpoort (Site 4), the mean ASPT score shows that there is some deterioration in the water quality. Finally, for Burgersfort Bridge (Site 5), the mean ASPT score indicates that there is major deterioration in the water quality. Primer statistical analysis indicated that the average dissimilarity between sites showed that the highest dissimilarity was between Tiershoek (Site 1) and Burgersfort Bridge (Site 5) which was conclusive with the results from the macro-invertebrate count and SASS, indicating that there is diverse difference from upstream to downstream. CCA indicated positive correlations between nutrients detected at Steelpoort with Athericidae, Tabanidae, Gomphidae, Baetidae, Elmidae, Planaria, Psephenidae, and Libellulidae which was indicated that water chemistry characteristics exert influence on macroinvertebrates. The results showed that there is degradation of the water quality in river from upstream to downstream with more pollution tolerant species being abundant at Steelpoort (Site 4) and Burgersfort Bridge (Site 5). The most favourable season was autumn and the least summer/spring and this may be attributed to the life cycle of the macro-invertebrate communities / NRF VLIR

Thesis (M.Sc. (Zoology)) --University of Limpopo, 2014 / Contamination of aquatic ecosystems by agricultural and mining activities, as well as by industrial discharges and urbanization in the catchment of the South African river systems has been the cause of increasing public concern. These activities may result in water pollution. One such river is the Olifants River System in Mpumalanga and Limpopo provinces which is highly impacted. The main aim of the study was to assess the impact of the water and sediment quality on the health of Clarias gariepinus and Labeo rosae and human risk when the fish is consumed at the Phalaborwa Barrage in the Lower Olifants River, Limpopo Province. This was achieved by assessing the water and sediment quality of the barrage at the three sampling sites; assessing the condition of the fish and the fish parasites by applying the fish HAI (Health Assessment Index) and PI (Parasite Index); determining the bioaccumulation of selected metals in the muscle tissue of the two fish species; and to determine the Human health risk factor upon consumption of fish contaminated with metals at the barrage. Ten fish from each fish species were collected seasonally at each site using gill nets of different mesh sizes. Standards methods were followed when testing selected water and sediment constituents. For water quality sampling, the water samples were collected over four seasons (autumn, winter, spring and summer) at three sites (inflow, wall and below wall) from April 2010 to January 2011. Sediment samples were also collected using a Friedlinger mudgrab (225cm3) at the three sites during winter and summer. Fish hosts were examined for mobile ectoparasites, weighed and measured. Blood samples were drawn and skin smears were made. Fish were killed, dissected and all external and internal organs were examined as prescribed in the fish health assessment index. The condition factor was determined for each fish population. All parasites were collected, fixed and preserved using standard methods. The highest water temperature (28.5 ºC) was in spring and lowest in winter (18 ºC). Overall pH was in an alkaline condition as it ranged from 7.4 to 8.7. Most water quality parameters were recorded at higher concentration in spring which includes; water temperature, pH, conductivity, salinity, TDS, alkalinity, and turbidity. Major ions (cations and anions) recorded were all within the TWQR. Sulphates concentrations were all within the TWQR. Calcium concentration levels exceeded the typical concentration limit in spring but the levels were still within the TWQR for domestic use. Nutrients levels (nitrate, nitrite, sulphate) were very low which indicate oligotrophic conditions. Highest total nitrogen was recorded in spring which is an indicative of eutrophic conditions. Highest phosphorous concentrations were recorded in winter, spring and summer which are an indicative of eutrophic conditions. Noticeable elevated levels were recorded at the inflow in summer which is an indicative of hypertrophic conditions. The results of the metals concentrations analysed demonstrated that metals within the barrage are present in trace amounts in the water. Analysis of the metal concentrations in water, sediment and fish muscle tissue revealed that the sediment contained the highest concentrations of metals followed by fish tissue and then the water. Metals that were detected in the water column includes; aluminium, antimony, arsenic, barium, boron, iron, manganese, selenium, strontium and tin. Metals that were detected at concentrations above the TWQR for aquatic ecosystem were; aluminium, antimony and selenium. Arsenic, cadmium and chromium were recorded at concentrations above the detection limit as suggested by CCME. Zinc concentrations were recorded at levels below suggested detection limit. Aluminium, barium, boron, cadmium, chromium, manganese, selenium and strontium were all detected at elevated levels in water and above the TWQR. Among the metals recorded in the water column, significant seasonal variations in concentration were found for aluminium, barium, boron, lead selenium and strontium whereas only boron showed a significant variation between sites. In comparison to the metals concentrations accumulated in the muscle tissue of both fish species. It was noted that C.gariepinus accumulated more metals than L. rosae; however L. rosae accumulated more metals at elevated concentrations than C. gariepinus. The metals that were accumulated at elevated levels in C. gariepinus were barium, boron, zinc and selenium. In L. rosae, iron, aluminium, strontium, titanium, vanadium and arsenic accumulated at elevated levels. All these metals pose a high risk to fish and human’s health. The highest population HAI was recorded in summer for both fish species. The lowest HAI value was recorded in autumn for both fish species. Although a high HAI population value was recorded higher in summer for both fish species, in general both fish species from the barrage were in a normal condition. A high number of ectoparasites were recorded in L. rosae than in C. gariepinus while high numbers of endoparasites were recorded in C. gariepinus than L. rosae. The dominating ectoparasites for both species were from the class monogenea. Although the prevalence for Contracaecum sp. in C. gariepinus was 100% in all season, it did not influence the condition of the host. None of the parasites identified from both fish species neither reached alarmingly infection levels nor caused any visible damage to the host. In conclusion, the water quality at the Phalaborwa Barrage is slightly polluted based on the water quality parameter(phosphorous) presence and recorded of some metals at the inflow that were recorded at elevated levels above the TWQR. Further recommendations are refereed such as extension of this study to all tributaries and to include other fish species in addition to constant monitoring of the impoundment.

Thesis (MSc. (Zoology)) -- University of Limpopo, 2014 / The Olifants River is presently one of the most threatened river systems in South Africa. The Upper and Middle catchments are heavily impacted by anthropogenic activities, however little is known of the status of the river in the Lower catchment in the Limpopo Province. Thus the aim of this study was to evaluate the impact of water quality on the health of Oreochromis mossambicus and Schilbe intermedius at the Phalaborwa Barrage. This was achieved through assessing the water (seasonally) and sediment quality (bi-annually) at three sites in the Phalaborwa Barrage (inflow, middle and the wall). Ten specimens of each of the two selected fish species were seasonally collected using gill nets of different mesh sizes from May 2010 to January 2011. The water, sediment and the dorsal muscle tissues from both fish species were analysed for selected metals at an accredited laboratory by means of ICP-OES spectrometry and the human health risk factor upon consumption of fish contaminated with metals was assessed. Fish health was determined at the field laboratory by applying the HAI, PI and IPI. In addition, the condition factor (CF) was determined for the selected fish species during all seasons. All water constituents with the exception of turbidity during spring (wall), anions (Cl, F and SO4) and cations (Ca, K, Mg and Na) fell within the target water quality range (TWQR) for aquatic ecosystems throughout the study. Inorganic nitrogen concentrations showed eutrophic (spring) and oligotrophic conditions (autumn, winter and summer), while phosphorus indicated eutrophic (autumn, winter and spring) and hypertrophic (summer) conditions throughout the study. There was no significant difference in anions (F=0.07; df=3; p=0.97), cations (F=0.57; df=3; p=0.64) and nutrients (F=0.79; df=3; p=0.56) detected in water. The metals that were detectable in the water samples were: Al, Fe, Sn, B, Sr, Se, Ba, Mn, Sb and As, while in sediment all metals (Fe, Al, Ti, Mn, Ba, B, Zn, Ag, V, Cr, Ni, Sr, Sn, Co, Cu, Cd, Pb, As and Sb) were detected with the exception of Se. The average metal concentrations detected above the TWQR are; Al, Fe, Se, Sn, Sb and As, in the sediment only Cr and Cd were above suggested quality guidelines. There was no significant difference in metals detected in water (F=0.05; i df=3; p=0.98) and sediment (F=1.62; df=1; p=0.21). Higher HAI values were recorded for S. intermedius than O. mossambicus, indicating that O. mossambicus was in better health than S. intermedius. For S. intermedius, parasites contributed the most to the total HAI followed by abnormal liver conditions, haematocrit levels (internal variables) and abnormal gills (external variable). While for O. mossambicus, parasites, liver, haematocrit (internal variables), gills, eyes, fins and skin (external variables) contributed to the HAI values. There was no significant difference in HAI values for O. mossambicus (F=1.9; df=3; p=0.15) and S. intermedius (F=2.58; df=3; p=0.66) throughout the study. The PI and IPI for ectoparasites for both fish species, were higher than the PI for endoparasites. There was a significant difference for PI values of O. mossambicus (F=0.07; df=3; p=0.041) and S. intermedius (F=3.65; df=3; p=0.019) during the study. Oreochromis mossambicus had higher CF values than S. intermedius and both fish species had values that indicated good fish. Metals that were detectable in O. mossambicus muscle tissue included: Ba, B, Zn, Fe, Sr, Al, Mn, Cr, Ag, Pb, Ni, Cu, Se, V, Sb, Ti, Sn and Co, while for S. intermedius Ba, B, Zn, Fe, Al, Cr, Sr, Mn, Cu, As, Pb, Se, Sn, Ag, Ti, Ni, Sb and Co were recorded. There was no significant difference in bioaccumulation levels between the two fish species (F=1.412; df=3; p=0.250). The human health risk assessment indicated that fish muscle tissues are unsuitable for continuous (weekly/daily) consumption. As some carcinogenic metals i.e. Pb, Cr and Sb for O. mossambicus and Pb, As and Cr for S. intermedius were detected at HQ levels of more than 50 times the recommended value of one. In conclusion, the Phalaborwa Barrage is impacted by metals (Al, Fe, Se, Sn, Sb and As) and occasionally with nutrients. The water and sediment quality and metal bioaccumulation have confirmed the latter statement and to a lesser extent the HAI, PI and IPI. The human risk assessment done indicated that continuous consumption of fish by humans, especially O. mossambicus may have adverse effects on the health of humans.

M.Sc. (Environmental Management) / Wetlands play a significant role in our environment as they provide a variety of goods, services and benefits to living species ranging from humans, animals and plants to microorganisms. Despite their importance, wetlands have somewhat been neglected over the past few years which has led to a rapid deterioration of wetland conditions and functions. Wetlands provide unique functions that cannot be provided by any other ecosystem; their value was recognised in the 1960s. Prior to this realisation the value of wetlands had been seriously underestimated to the extent where they were even previously labelled as “wastelands”. The reality is that to date minimal measures have been put in place to assist in the rehabilitation and future conservation of wetlands. The lack of wetland management and monitoring can be attributed to the fact that very little is known about the functioning of some of the wetland systems. Endorheic wetlands have recently been emerging as ecosystems of importance. Very little is known about endorheic wetlands and their ecological functioning. To date a fair amount of studies have been conducted on the pans in Mpumalanga and in the Free State but minimal information exists on the pans in the North West Province. The objectives of this study were therefore to compare the abiotic and biotic composition of pans in Mpumalanga and North West Provinces, in order to contribute to the knowledge which will eventually assist in devising rehabilitation measures and future conservation of pans in the area. Three different water ecosystem components were studied; these included aquatic invertebrate communities, water quality and sediment characteristics. The collected water samples were taken to an accredited laboratory to be analysed. When compared between the two provinces, the water-quality results indicated differences between provinces as well as among individual pans. However, most of the pans in both provinces show characteristics of being dystrophic alkaline systems. The invertebrates were collected using sweep nets and stored in jars containing 5% neutrally buffered formalin and a staining agent (Rose Bengal). The sediment characteristics were determined by using standard techniques and results showed that there were no obvious similarities between the different pans in the different provinces. Water-quality analyses were performed on samples taken during both winter- and summer-sampling surveys and these samples were analysed by a reputable laboratory. Based on the analyses of the invertebrate community samples, 25 taxa were identified; results show similarities in the structure of communities in both provinces with the exception of one or two different species. Sampling was conducted over a period of two seasons at all sampling points and several species were found belonging to different families. Invertebrates sampled in Mpumalanga pans were similar to those reported in previous studies done in the area and most of the invertebrates sampled in Mpumalanga and the North West are known to be commonly found in temporary habitats. Spatial and temporal variations in invertebrate assemblages were determined; this analysis displayed differences in the different variables (biotic, physical and chemical) tested over the two seasons. The pans in Mpumalanga were dominated by coarse sand. Large amounts of coarse sand accompanied by poor water quality were observed in MP Pan A in Mpumalanga Province; this could be an indication of somewhat poor catchment management. The results of the abiotic and biotic comparison show that there are minor similarities and differences among the selected pans studied in each province. The knowledge acquired can now be utilised to enhance the available literature on these pans. Long-term studies have to be done to better understand the ecological functioning of the pans in the North West Province in order to devise mitigation measures as well as appropriate rehabilitation strategies and conservation measures.

CAPES / Este estudo avaliou a qualidade das águas e dos sedimentos da sub-bacia do rio Barigüi, Região Metropolitana de Curitiba, em relação à presença, disponibilidade química e potencial tóxico de espécies químicas (Al, Fe, Ti, K, Ca, P, S, Zr, Mn, Zn, Sr, Cu, Nb, Y, Rb, Ni, Cr, Cd e Pb) majoritárias e traços. Sedimentos de bacias urbanas são matrizes ambientais complexas e multielementares, que se tornaram objeto de estudo de muitas pesquisas devido ao caráter ativo. Este compartimento intercambia espécies químicas com a coluna d’ água afetando sua qualidade, influenciando sua toxicidade e interferindo na biota aquática. As quatro campanhas de amostragem foram realizadas em três pontos de modo a cobrir regiões distintas da sub-bacia, sendo estas sujeitas a diversos impactos ambientais devido à urbanização e industrialização. Para a quantificação de espécies químicas nos sedimentos e na coluna d’água fez-se uso das técnicas instrumentais Espectrometria de Absorção Atômica com Atomizador Chama (FAAS) e Espectrometria de Fluorescência de Raios-X por Energia Dispersiva (EDXRF), segundo protocolos 3030B (APHA), 3050B (USEPA) e 200.2 (USEPA). Parâmetros acessórios tais como potencial redox, pH, amônia, fósforo total e ortofosfato, alcalinidade total e clorofila-a foram determinados nas amostras de águas. As amostras de água também foram caracterizadas por espectroscopia de absorção molecular e por espectroscopia de fluorescência molecular. Estabeleceu-se o estado de trofia das águas por meio do Índice de Estado Trófico IET e compararam-se os valores determinados com os valores regulamentadores da resolução 357 de 2005 do CONAMA. Os sedimentos passaram por análises térmicas (TGA/DSC), granulométricas, de umidade (%) e determinaram-se seus indicies geoquímicos de qualidade. Os resultados permitiram diferenciar as regiões estudadas, e observar que as amostras de águas e sedimentos sofrem influência da urbanização e industrialização como os principais responsáveis pelas cargas poluentes. Nesse sentido, o ponto amostral de Araucária encontra-se mais degradado em relação aos de Almirante Tamandaré e Santa Felicidade sobre a sub-bacia do rio Barigüi-PR, indicando a necessidade de ações de gestão ambiental sobre o sistema hídrico. / This study evaluated the water and sediment quality of the Barigui River sub-basin, Greater Curitiba, in terms of the presence, chemical availability, and toxic potential of common chemical species as well as trace elements. Urban basin sediments are complex multi-element environmental matrices and have become the subject of many studies because of their active character. These matrices interchange chemical species with the water column, which affects its quality, influences its toxicity, and interferes with aquatic life. Four sampling operations were completed at three different sites, subject to several environmental impacts due to urbanization and industrialization, in order to cover distinct regions of the sub-basin. For the quantification of chemical species in the sediments and water column, flame-atomizer atomic absorption spectroscopy (FAAS) and energy-dispersive X-ray fluorescence spectroscopy (EDXRF) techniques were used, according to protocol 3030B (APHA), 3050B (USEPA) and 200.2 (USEPA). Auxiliary parameters such as redox potential, pH, ammonia, total phosphorus and orthophosphate, total alkalinity, and chlorophyll a were determined for the water samples. The water samples were also characterized by molecular absorption spectroscopy and molecular fluorescence spectroscopy. The trophic state of the water was established using the trophic state index (TSI) and the determined values were compared with the regulatory values pertaining to CONAMA (2005) resolution 357. The sediments were subjected to thermal analysis (TGA/DSC), particle size and moisture content (%) estimation, and geochemical quality index determination. The results allowed us to differentiate between the studied regions and to conclude that the water and sediment samples are influenced by urbanization and industrialization, which are the main agents responsible for pollution. In this context, the Araucária sample was more degraded than those in Almirante Tamandaré and Santa Felicidade in the Barigui River sub-basin – PR, indicating the need for environmental management in this water system.

CAPES / Este estudo avaliou a qualidade das águas e dos sedimentos da sub-bacia do rio Barigüi, Região Metropolitana de Curitiba, em relação à presença, disponibilidade química e potencial tóxico de espécies químicas (Al, Fe, Ti, K, Ca, P, S, Zr, Mn, Zn, Sr, Cu, Nb, Y, Rb, Ni, Cr, Cd e Pb) majoritárias e traços. Sedimentos de bacias urbanas são matrizes ambientais complexas e multielementares, que se tornaram objeto de estudo de muitas pesquisas devido ao caráter ativo. Este compartimento intercambia espécies químicas com a coluna d’ água afetando sua qualidade, influenciando sua toxicidade e interferindo na biota aquática. As quatro campanhas de amostragem foram realizadas em três pontos de modo a cobrir regiões distintas da sub-bacia, sendo estas sujeitas a diversos impactos ambientais devido à urbanização e industrialização. Para a quantificação de espécies químicas nos sedimentos e na coluna d’água fez-se uso das técnicas instrumentais Espectrometria de Absorção Atômica com Atomizador Chama (FAAS) e Espectrometria de Fluorescência de Raios-X por Energia Dispersiva (EDXRF), segundo protocolos 3030B (APHA), 3050B (USEPA) e 200.2 (USEPA). Parâmetros acessórios tais como potencial redox, pH, amônia, fósforo total e ortofosfato, alcalinidade total e clorofila-a foram determinados nas amostras de águas. As amostras de água também foram caracterizadas por espectroscopia de absorção molecular e por espectroscopia de fluorescência molecular. Estabeleceu-se o estado de trofia das águas por meio do Índice de Estado Trófico IET e compararam-se os valores determinados com os valores regulamentadores da resolução 357 de 2005 do CONAMA. Os sedimentos passaram por análises térmicas (TGA/DSC), granulométricas, de umidade (%) e determinaram-se seus indicies geoquímicos de qualidade. Os resultados permitiram diferenciar as regiões estudadas, e observar que as amostras de águas e sedimentos sofrem influência da urbanização e industrialização como os principais responsáveis pelas cargas poluentes. Nesse sentido, o ponto amostral de Araucária encontra-se mais degradado em relação aos de Almirante Tamandaré e Santa Felicidade sobre a sub-bacia do rio Barigüi-PR, indicando a necessidade de ações de gestão ambiental sobre o sistema hídrico. / This study evaluated the water and sediment quality of the Barigui River sub-basin, Greater Curitiba, in terms of the presence, chemical availability, and toxic potential of common chemical species as well as trace elements. Urban basin sediments are complex multi-element environmental matrices and have become the subject of many studies because of their active character. These matrices interchange chemical species with the water column, which affects its quality, influences its toxicity, and interferes with aquatic life. Four sampling operations were completed at three different sites, subject to several environmental impacts due to urbanization and industrialization, in order to cover distinct regions of the sub-basin. For the quantification of chemical species in the sediments and water column, flame-atomizer atomic absorption spectroscopy (FAAS) and energy-dispersive X-ray fluorescence spectroscopy (EDXRF) techniques were used, according to protocol 3030B (APHA), 3050B (USEPA) and 200.2 (USEPA). Auxiliary parameters such as redox potential, pH, ammonia, total phosphorus and orthophosphate, total alkalinity, and chlorophyll a were determined for the water samples. The water samples were also characterized by molecular absorption spectroscopy and molecular fluorescence spectroscopy. The trophic state of the water was established using the trophic state index (TSI) and the determined values were compared with the regulatory values pertaining to CONAMA (2005) resolution 357. The sediments were subjected to thermal analysis (TGA/DSC), particle size and moisture content (%) estimation, and geochemical quality index determination. The results allowed us to differentiate between the studied regions and to conclude that the water and sediment samples are influenced by urbanization and industrialization, which are the main agents responsible for pollution. In this context, the Araucária sample was more degraded than those in Almirante Tamandaré and Santa Felicidade in the Barigui River sub-basin – PR, indicating the need for environmental management in this water system.